<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        var s = new Set();
        s.add(100);
        s.delete(100);
        console.log(s);

        var mySet = new Set();
        mySet.add("5")
        var flag = mySet.has("5");  //判断是否含有某个数值has()
        console.log(flag); // true


        var mySet = new Set();
        mySet.add("5")
        mySet.clear();
        console.log(mySet); // Set(0){size: 0}


    </script>

</body>

</html>